Rotary pump



N'. N'ILSON.

ROTARY PUMP (No Model.)

No. 452,726. Patented May 19, 1891.

@MWew UNITED STATES PATENT OEEICE.

NILS NILSON, OF MINNEAPOLIS, MINNESOTA.

ROTARY Pu M P.

SPECIFICATION forming part of Letters Patent No. 452,726, dated May 19,1891. Application iiled December 19, 1887. Serial No. 258,279. (Nomodel.)

T0 all wto'n't it Hefty concern:

Be it known that I, NILs NILSON, of Minneapolis, in the county ofHennepin and State of Minnesota, have invented certain new and usefulImprovements in Rotary Pumps, of which the following is a specification.

My invention relates to rotary pumps with usual inlet and outlet portsand avalve opening and closing the outlet-port acted upon by aneccentric cylindrical piston.

The object of my invention is to simplify the construction of suchpumps, diminish the cost, diminish the friction and wear' of parts, andthereby economize lthe power and increase the durability and efficiencyof the pump.

My invention consists, generally, in the combination, in a rotary pump,of a rotating cylindrical piston mounted upon an eccentric core or axis,so as to roll upon the inner surface of the pum p-barrel in onedirection while being carried in an opposite direction by the turning ofthe shaft.

The invention also consists in a swinging valve attached to thepump-barrel, riding upon the piston and alternately opening and closingthe outlet-port of the pump, the pump being adapted for use'either as asuction or` force pump by the addition of aproper valve in either theinlet or outlet to prevent a return-flow of the iiuid without differencein construction, as clearly appears from the accompanying drawings andfollowing description.

specification, Figure l shows the interior and working parts of myimproved pump exposed to view by the removal of the head of thepump-barrel. Fig. 2 represents a vertical cross-section, and Fig. 3 alongitudinal section, of the same.

In the drawings, l represents the pumpbarrel with its inlet-and outletports 9 and l0, and recessed at 1l to receive the swinging valve 7.

3 is the pumpshaft concentric with the pump-barrel, iiattened to iitinto a slot in the eccentric cylinder 4, the eccentricityof which isadjusted by the set-screw 5, passing through the cylinder into the slot,carrying upon its point a plate 14:, covered with a strip of packing 6,and pressing this against the shaft.

In the said drawings, forming a part of this 12 is the rotary pistonconcentric with the cylinder 4 and turning upon it as its axis, androlling upon the inner surface of the pump-barrel.

rllhe action of the pump in operation is as follows: The set-screw 5being adjusted so as to cause the piston .to bear upon the barrel of thepump, the shaft 3, on being turned in the direction indicated by thearrow I4, carries with it the eccentric cylinder 4 and the piston l2,but the piston freely turning upon the eccentric, caused by its bearingupon the inner surface of the pu nip-barrel to roll upon the said barrelin the direction indicated by the arrow l5, the water being by thetraveling of the pistou drawn in at 9 and forced out at lO. The swingingValve 7, hinged at 8, always rides upon the surface of the piston, beingheld in such position by its own weight or by a spring 13 or otherequivalent device. The valve is grooved on its upper surface, as shown,and fits loosely,-so that all the fluid as forced toward it finds freevent through the space in said recess and through the groove out of theport while the valve is in the act of closing, thus avoiding increasedfriction fromthe resistance of confined fluid. As the piston rollsforward it lifts the valve into its recess, and in passing allows ittodrop back and reopen the port. By the set-screw 5, as indicated, theeccentric can be nicely adj usted, so that the piston will fit in androll upon the inner surface of the barrel and compensation be madefor'the gradual wear of parts. By the rolling instead of sliding of thepiston friction between it and the pumpbarrel is almost whollyeli-miminated, while the direction of the turn of the piston makes thefriction against thevalve slight, and the wear of the valve in no wayaffects its working efliciency.

What I claim as my invention, and desire to secure by Letters Patent,isy In a rotary pump, the combination, with the pump-barrel fitted withports and valve, of an eccentric cylinder 4, formed with one slot toreceive a flattened shaft and another slot to receive the head of ascrew below the periphery of the cylinder, a shaft 3, lying in the slottherefor in said cylinder, a plate 14, packing 6 between said plate andcylinder, set-screw IOO 5, having its head lying within the recess Intestimony whereof I have hereunto set therefor in said cylinder and itsend bearing my hund this lith day of December, 1887. against said plate,und the ring-piston 12, mounted upon said cylinder to roll upon the NILSNILSON. 5 inner surface of the pump-barrel in an opposite direction fromthe revolution of the In presence of# shaft, substantially as and forthe purposes R. H. SANFORD, set forth. A. M. GASKELL.

